KR20030040156A - Composite material and method for manufacturing the same - Google Patents

Abstract

PURPOSE: To prevent the occurrence of cracks, ballooning, peeling and voids in a laminating layer when a plated composite material is laminated to an other material by the use of the laminating layer such as a solder layer. CONSTITUTION: After masked, the composite base material is pretreated. Then, the surface of the composite base material is activated, and a metal catalyst is imparted onto the laminated surface of the composite base material and the surface of a masking tape, and thereafter, plated layers are formed on the laminated surface of the composite base material and the surface of the masking tape by electroless plating treatment. The preferable thickness of the plated layers is 5 to 100 μm. After removed the masking tape, the composite base material having the plated layer only on the laminated surface is subjected to drying treatment.

Description

Composite materials and its manufacturing method {COMPOSITE MATERIAL AND METHOD FOR MANUFACTURING THE SAME}

The present invention relates to a composite material having a composite material in which a porous sintered body is impregnated with metal, and bonded to another object by a bonding layer, and a method of manufacturing the same.

Recently, as a constituent material of a heat sink used for an IC chip equipped with a CPU, not only the thermal conductivity is considered, but also the selection of a material having a high thermal conductivity that almost coincides with the thermal expansion coefficient of silicon or GaAs, which is a semiconductor substrate. This is needed.

There are various reports on the improvement of the heat sink material, for example, examples using aluminum nitride (AlN), examples using Cu (copper) -W (tungsten), and the like. AlN is excellent in the balance between thermal conductivity and thermal expansion, and particularly close to the thermal expansion coefficient of Si, and is therefore suitable as a heat sink material for semiconductor devices using a silicon substrate as a semiconductor substrate.

Cu-W is a composite material having low thermal expansion of W and high thermal conductivity of Cu. Furthermore, Cu-W is suitable as a constituent material of a heat sink having a complicated shape in view of ease of sintering and molding.

As another example, a ceramic substrate containing SiC as a main component contains metal Cu in a proportion of 20 to 40% by volume (see Japanese Patent Application Laid-Open No. 8-279569), or a powder sintered porous body made of an inorganic material ( A porous sintered body) impregnated with 5 to 30% by weight of Cu (see Japanese Patent Laid-Open No. 59-228742) and the like have been proposed.

By the way, when using the composite material which impregnated the porous sintered compact as a heat sink, the composite material is bonded to the semiconductor circuit or the substrate by soldering, that is, soldering or brazing.

However, the above-mentioned composite material has a problem that the wettability (solderability, brazing property) with respect to solder or a brazing material is not good. Therefore, in order to improve the wettability of the composite material, it is thought that forming a plating layer on the surface of the composite material is effective.

When a plating layer is formed in a composite material, the following new problem arises. That is, some residual pores exist in the above-described composite material. For this reason, residual liquid (processing grinding liquid or plating liquid) penetrates into the residual pores, and it vaporizes at the time of soldering, and voids (residual bubbles) are generated in the solder layer.

Specifically, when the thickness of the plating layer formed on the surface of the composite material is thin, the unbonded portion of the plating layer is dotted, and voids are likely to occur during soldering. On the contrary, when the plating layer is thickened, expansion or peeling occurs due to the stress during vaporization and expansion of the residual liquid during soldering, and heat transfer between the material and the plating layer cannot be obtained.

SUMMARY OF THE INVENTION The present invention has been made in view of such a problem, and when the plated composite material is bonded to another object by a bonding layer such as a solder layer, cracks, swelling or peeling of the plating layer and voids are generated in the bonding layer. It aims at providing the composite material which can suppress things, etc., and its manufacturing method.

1 is a perspective view showing a partially broken composite material according to the first embodiment;

2 is a cross-sectional view showing an example of the configuration when a composite material of the composite material according to the first embodiment is used as a heat sink material.

3 is a process block diagram showing a first manufacturing method.

4 is a table describing the details of each process (first table).

5 is a table (second table) describing the details of each process.

6 is a table describing the details of each process (third table).

7 is a table describing the details of each process (fourth table).

8 is an explanatory diagram showing a state in which a masking tape is peeled off in a first manufacturing method.

9 is a sectional view of a composite material according to a second embodiment.

10 is a process block diagram illustrating a second manufacturing method.

11 is a process block diagram showing a manufacturing method according to a modification of the second manufacturing method.

12 is an explanatory diagram showing another method of masking.

13 is a cross-sectional view showing a composite material according to the third embodiment.

14 is a process block diagram showing a third manufacturing method.

15 is a cross-sectional view showing a composite material according to the fourth embodiment.

16 is a process block diagram showing a fourth manufacturing method.

17 is a table showing details of Comparative Example 1 and Comparative Example 2 and Examples 1 to 4 used in the Experimental Example.

18 is a table showing the results of an experimental example.

<Explanation of symbols for the main parts of the drawings>

10A-10D: Composite material

12: porous sintered body

14: metal

16: composite material

18: plating layer

18a: thick plating layer

18b: thin plating layer

The composite material according to the present invention is a composite material having a composite material impregnated with a porous sintered body and bonded to another object by a bonding layer, wherein a plating layer is formed on at least a portion of the surface of the composite material on which the bonding layer is formed. It is characterized by that.

According to this, the liquid remaining in the composite material (cutting liquid or plating treatment liquid, etc.) is vaporized and flowed out as a gas when it is bonded to another object through the bonding layer. At this time, the vaporized gas acts as a resistor in relation to permeation. The plating layer flows out from a portion where the plating layer is not formed or a portion where the plating layer is thinly formed, avoiding the plating layer.

Therefore, in the present invention, cracks, swelling and peeling of the plating layer and voids in the bonding layer are suppressed due to the outflow of the vaporized gas.

The plating layer may be composed of only the first plating layer, or may be composed of the first plating layer and the second plating layer. In this case, the first plating layer may be formed on at least a portion of the surface of the composite material on which the bonding layer is formed, and the second plating layer may be formed on a portion other than the above, or at least the surface of the composite material. The said 1st plating layer is formed in the part in which a joining layer is formed, and the structure in which the said 2nd plating layer is not formed in the other part is also employ | adopted preferably.

It is preferable to form the said 1st plating layer so that the void ratio which may generate | occur | produce in the said bonding layer by the vaporization gas which permeate | transmits the 1st plating layer may be 5% or less, Preferably it is 3% or less. Or, it is preferable that the first plating layer does not transmit the vaporization gas of the residual liquid.

In addition, the first plating layer is preferably formed so that the volume of the vaporized gas that passes through the first plating layer is 5% or less, preferably 3% or less of the volume of the bonding layer, and the leakage property of the first plating layer is It is preferable that it is 5.0x10 <^-10> cc-atm / sec or less, Preferably it is 2.0x10 <^-10> cc-atm / sec or less.

In addition, the first plating layer completely covers the open pores present on the surface of the composite material, or covers the open pores by 90% or more by area ratio, or covers the open pores by 95% or more by area ratio. Or 99% or more of the open pores in an area ratio.

The first plating layer may be a layer formed by electroless plating at least on the outermost surface. In this case, it is preferable that the said 1st plating layer is a layer by (1) electroless plating, and there should be no plating crack, or (2) a layer by electroless plating, and hardness is 80% or less of maximum hardness.

At least the outermost surface of the first plating layer may be a layer by electroplating. In this case, it is preferable that at least the outermost surface of the first plating layer contains Ni.

Moreover, the said 1st plating layer may be comprised by the layer by electroless plating and the layer by electrolytic plating.

In addition, the first plating layer preferably has a thickness that does not permeate the vaporization gas, or a thickness of at least twice the diameter of the open pores present on the surface of the composite material. Specifically, the first plating layer has a thickness of 5 to 100 µm, preferably 5 to 50 µm, more preferably 5 to 30 µm, and more preferably 15 to 25 µm.

In addition, the first plating layer may be formed by repeating a series of processes n times of drying after the plating treatment.

On the other hand, it is preferable that the said 2nd plating layer is thickness which a residual liquid is easy to vaporize and remove, and it is preferable to permeate the vaporization gas of a residual liquid at least more than the said 1st plating layer. Specifically, the second plating layer has a thickness of 10 μm or less, preferably 5 μm or less, and more preferably 3 μm or less.

The leakage property of the second plating layer is preferably 5.0 × 10 ⁻¹⁰ cc-atm / sec or more, preferably 1.0 × 10 ⁻⁹ cc-atm / sec or more.

The second plating layer may be a layer by electroless plating or may be a layer by electroplating. Or you may be comprised by the layer by electroless plating and the layer by electrolytic plating.

In addition, the plating layer may be formed into a thin film by processing at least portions other than the portion where the bonding layer is formed by etching or polishing.

Next, the manufacturing method of the composite material which concerns on this invention is a manufacturing method of the composite material which has a composite material in which a porous sintered compact was impregnated with a metal, and is bonded to another object by a bonding layer, WHEREIN: And a step of forming a plating layer on a portion where the bonding layer is formed.

According to this, cracks, swelling and peeling of the plating layer and voids in the bonding layer are suppressed due to the outflow of the vaporization gas of the liquid remaining in the composite material, thereby improving the quality and yield of the composite material. have.

The plating layer may be formed of only the first plating layer or may be formed of the first plating layer and the second plating layer.

In this case, the first plating layer may be formed on at least a portion of the surface of the composite material on which the bonding layer is formed, and the second plating layer may be formed on a portion other than that, or at least on the surface of the composite material. It is not necessary to form the said 1st plating layer in the part in which the said joining layer is formed, and to form the said 2nd plating layer in the other part.

In addition, the present invention may include a step of preventing the plating layer from being formed on the surface other than the portion for forming the first plating layer, or masking the surface other than the portion for forming the first plating layer. You may also include a process.

In addition, the present invention may include a step of forming a first plating layer after the masking treatment is performed on the second plating layer other than the portion forming the first plating layer after the second plating layer is formed. After forming 1 plating layer, you may process at least parts other than the part in which the said joining layer is formed by etching or polishing.

And after forming the said plating layer, it is preferable to perform a drying process. In this case, the drying treatment is preferably carried out at a temperature and time at which moisture can be vaporized off at least.

Specifically, the drying treatment is preferably maintained at an arbitrary temperature of 30 to 600 ° C. for an arbitrary time of 1 to 300 minutes, more preferably at 1 to 300 minutes at an arbitrary temperature of 200 to 400 ° C. It may be maintained for a time, or more preferably at an arbitrary temperature of 200 to 300 ° C. for an arbitrary time of 1 to 120 minutes.

Moreover, it is preferable to perform the said drying process in the atmosphere which suppresses oxidation of the said plating layer. In this case, the atmosphere can be selected from an inert gas atmosphere, a vacuum atmosphere and a reducing atmosphere. In particular, when the reducing atmosphere is selected, hydrogen is preferably 3% or more, more preferably hydrogen is 30% or more, and more preferably hydrogen is 90% or more.

Moreover, it is preferable to perform the said drying process at the temperature increase rate which does not produce expansion | swelling in the said 1st plating layer and a 2nd plating layer. In this case, it is preferable that the said temperature rise rate is 400 degrees C / hour or less, More preferably, it is 100 degrees C / hour or less, More preferably, it is 50 degrees C / hour or less.

Moreover, it is preferable to perform the said drying process by the heating program maintained near the vaporization temperature of a residual liquid.

In addition, the first plating layer and the second plating layer may be formed by repeating a series of treatments n times after drying. In this case, before performing the said plating process, it is preferable to perform the process which gives a metal catalyst to a to-be-plated surface, or the process which activates a to-be-plated surface.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of the composite material which concerns on this invention, and its manufacturing method is demonstrated, referring FIGS.

First, the composite material 10A according to the first embodiment is a composite in which the metal 14 is impregnated into the porous sintered body 12 obtained by pre-firing and networking carbon or its allotrope or SiC as shown in FIG. 1. The plating layer 18 is formed in the surface of the raw material 16, and is comprised. As the metal 14, at least one selected from CU, Al, Ag, or an alloy thereof is used.

In this case, as the carbon or its allotrope or SiC, the thermal conductivity is 100 W / mK or more, preferably 150 W / mK or more (estimated value in the absence of pores), more preferably 200 W / mK or more (pores) ) Is preferably used.

In this example, the composite material 16 in which copper is impregnated into the open pores of the porous sintered body 12 made of graphite or SiC having a thermal conductivity of 100 W / mK or more is shown. As the metal 14 to be impregnated, aluminum and silver can be used in addition to copper.

The volume ratio of the porous sintered body 12 and the metal 14 is in the range of 50% by volume to 80% by volume for the porous sintered body 12 and 50% by volume to 20% by volume for the metal 14. Thereby, the composite raw material 16 whose thermal conductivity is 180-220 W / mK or more, and whose thermal expansion coefficient is 4 * 10 <^-6> / degreeC-7 * 10 <^-6> / degreeC can be obtained.

The porosity of the porous sintered body 12 is preferably 10% by volume to 50% by volume. If the porosity is 10 vol% or less, the thermal conductivity of 180 W / mK (room temperature) cannot be obtained. If the porosity is more than 50 vol%, the strength of the porous sintered compact 12 is lowered, and the thermal expansion coefficient is 15.0 × 10 ^-6 / ° C or less This is because it cannot be suppressed.

As for the average open pore diameter (pore diameter) value of the said porous sintered compact 12, 0.1-200 micrometers is preferable. If the pore diameter is less than 0.1 µm, it is difficult to impregnate the metal 14 in the open pores and the thermal conductivity is lowered. On the other hand, when the said pore diameter exceeds 200 micrometers, the intensity | strength of the porous sintered compact 12 falls, and thermal expansion rate cannot be suppressed low.

As distribution (pore distribution) related to the average open pore of the said porous sintered compact 12, it is preferable to distribute 90 volume% or more in 0.5-50 micrometers. If the pores of 0.5 to 50 µm are not distributed at 90% by volume or more, open pores in which the metal 14 is not impregnated may increase, resulting in a decrease in thermal conductivity.

Moreover, it is preferable that the closed porosity of the composite raw material 16 obtained by impregnating the metal 14 in the porous sintered compact 12 is 5 volume% or less. It is because there exists a possibility that thermal conductivity will fall when it exceeds 5 volume%.

In addition, the automatic porosimeter (brand name "autopoa 9200") manufactured by Shimadzu Corporation was used for the measurement of the said porosity, pore diameter, and pore distribution.

In the composite material 10A according to the first embodiment, for example, when graphite is used, it is preferable to add an additive that reduces the waste porosity when the graphite is prebaked. SiC and / or Si can be mentioned as this additive. Thereby, the waste hole (closed pore) at the time of baking can be reduced, and the impregnation rate of the metal 14 with respect to the porous sintered compact 12 can be improved.

Moreover, you may make it add the element which reacts with this graphite and forms a carbide layer in graphite. As this additional element, 1 selected from Nb, Cr, Zr, Be, V, Mo, Al, Ta, Mn, Si, Fe, Co, Ni, Mg, Ca, W, Ti, B, and misch metal Or more species. Accordingly, upon firing the graphite, a reaction layer (carbide layer) is formed on the surface of the graphite (including the surface of the open pores), and the wettability with the metal 14 impregnated in the open pores of the graphite is improved. Impregnation at low pressure becomes possible, and impregnation with fine open pores is also possible.

On the other hand, it is preferable to add at least one selected from Te, Bi, Pb, Sn, Se, Li, Sb, Tl, Ca, Cd and Ni to the metal 14 impregnated in the porous sintered body 12. As a result, the wettability of the interface between the porous sintered body 12 and the metal 14 is improved, and the metal 14 easily enters the open pores of the porous sintered body 12. In particular, Ni has the effect of being easy to dissolve carbon and easy to impregnate.

In addition, it is preferable to add at least one selected from Nb, Cr, Zr, Be, Ti, Ta, V, B, and Mn to the metal 14 impregnated into the porous sintered body 12. According to this, the reactivity of the graphite and the metal 14 is improved, and the graphite and the metal 14 easily adhere to each other in the open pores, thereby suppressing the generation of waste holes.

Further, to the metal 14 impregnated in the porous sintered body 12, at least one selected from an element having a solid / liquid temperature range of 30 ° C or higher, preferably 50 ° C or higher, such as Sn, P, Si, Mg, is added. It is desirable to. This can reduce the variation during impregnation. It is also preferable to add an element for lowering the melting point to the metal 14. This addition element is, for example, Zn.

However, residual pores are somewhat present in the composite material 16 described above. For this reason, when the plating layer 18 is formed on the surface of the composite material 16, the processing grinding liquid or the plating treatment liquid penetrates into the residual pores, and is usually vaporized at the time of soldering to void (residual bubbles in the solder layer). ) Will occur.

However, in the first embodiment, the plating layer 18 on the surface of the composite material 16 is formed by following the steps below. That is, the plating layer 18 is formed in the part in which the said solder layer is formed in the surface of the composite raw material 16 at least.

For example, assuming that the composite material 16 is used as the heat sink material, as shown in FIG. 2, the IC chip 22 is formed on the composite material 16 through the insulating substrate 20. Although mounted, the bonding of the insulating substrate 20 to the composite material 16 and the bonding of the IC chip 22 to the insulating substrate 20 are performed by the solder layer 24, for example. Therefore, in order to improve the wettability of the solder layer 24 of the composite material 16, the plating layer (for example, the upper surface) is formed on the joint surface 16a (for example, the upper surface) on which the solder layer 24 is formed. 18) and the plating layer 18 is not formed on the other surface (for example, the lower surface and the four side surfaces).

Here, the specific example (first manufacturing method) of the manufacturing method of the composite material 10A which concerns on 1st Embodiment is demonstrated, referring FIGS. 3-8.

In the first manufacturing method, first, in the step S1 of FIG. 3, the composite material 16 in which the metal 14 is impregnated into the porous sintered body 12 obtained by pre-firing and networking carbon or its allotrope or SiC is fabricated. .

Thereafter, the composite material 16 is masked in step S2. This masking is, for example, as shown in the "(1) masking" process of FIG. 4, in the surface (for example, lower surface and four sides) except the joining surface 16a among the surfaces of the composite material 16 which is a substantially rectangular parallelepiped shape. Apply masking tape. Of course, a conventional photoresist film or the like can be used instead of the masking tape.

Thereafter, in step S3, the masked composite material 16 is pretreated. As this pretreatment, for example, as shown in the "(2) pretreatment" process of FIG. 4, an alkali degreasing process and a cleaner conditioner process are mentioned. Examples of chemicals, concentrations and temperatures used in this pretreatment are shown in FIG. 4. In this Fig. 4, UF-80K and ACL-009 are both drugs manufactured by Uemura Industries.

Thereafter, the surface of the composite material 16 is activated in step S4 of FIG. As this activation process, for example, as shown in the "(3) activation 1" process of FIG. 4, an etching process and an pickling process are mentioned. Examples of the chemicals, concentrations, and temperatures used in this activation treatment are shown in FIG. 4.

Then, in the case where the electroless plating treatment is performed thereafter, prior to the electroless plating treatment, a metal catalyst is applied to at least the joint surface 16a of the composite material 16 in step S5 of FIG. 3. The conditions (chemical, concentration, temperature) to which this metal catalyst is applied are shown, for example in the "(4) catalyst application" process column of FIG. In this Fig. 4, PED-104, AT-105 and AT-106 are all chemicals manufactured by Uemura Industries.

In addition, when electrolytic plating process is performed instead of electroless plating process, the said process (step S5 of FIG. 3) can be skipped as mentioned later. Thus, in Figure 3 step S5 is described in parentheses.

Thereafter, electroless plating is performed in step S6 of FIG. 3 to form the plating layer 18 on at least the bonding surface 16a of the composite material 16. This electroless plating treatment is, for example, performing electroless plating treatment of NiB after performing electroless plating treatment of NiP, as shown in the “(5) Electroless Plating” process of FIG. 5. The conditions of these electroless plating processes are shown in FIG. In FIG. 5, Nimuden SX, SX-M, SX-A, BEL-980, BEL-980M, BEL-980S, BEL-980P, BEL-980T, and BEL-980R are all chemicals manufactured by Uemura Industries. .

The thickness t (see FIG. 8) of the plating layer 18 may be such that the vaporization gas of the liquid remaining in the composite material 16 does not penetrate the plating layer 18, or exists in the composite material 16. It is desirable to have a thickness that can cover the open pores. Here, the thickness of the extent which can cover the open pores which exist in the composite raw material 16 means the thickness of about twice the average diameter of the open pores which exist in the composite raw material 16. As shown in FIG.

In view of the permeability (leakage) of the vaporized gas, the leakage of the plating layer 18 is preferably 5.0 × 10 ^-10 cc-atm / sec or less, more preferably 2.0 × 10 ^-10 cc-atm / sec or less .

Specifically, the thickness t of the plating layer 18 is 5-100 micrometers, Preferably it is 5-50 micrometers, More preferably, it is 5-30 micrometers, More preferably, it is 15-25 micrometers.

Thereafter, in step S7 of FIG. 3, the masking tape is peeled off. This process can be performed simply by holding the side surface of the composite material 16 plated using tweezers or the like, exposing the masking tape from the plating layer 18, and then removing the masking tape. By this peeling process, as shown in FIG. 8, the plating layer 18 remains only in the bonding surface 16a of the composite raw material 16. As shown in FIG.

When the photoresist film is used instead of the masking tape, the plated composite material 16 is immersed in a liquid in which the photoresist film is dissolved. By this treatment, the plating layer 18 formed on the surface of the photoresist film is removed like the photoresist film (lift off method), and as a result, the bonding surface 16a of the composite material 16 is shown in FIG. ), The plating layer 18 remains.

Thereafter, in step S8 of FIG. 3, a drying treatment is performed on the composite material 16 having the plating layer 18 formed on the bonding surface 16a. As shown in the "(8) drying" process of FIG. 6, this drying process is what performs this drying after preliminary drying. The conditions of predrying and this drying are shown in FIG. It is preferable to perform this drying process in atmosphere which suppresses oxidation of the plating layer 18, for example, reducing atmosphere, inert gas atmosphere, and vacuum atmosphere. That is, it is preferable that this drying process is performed on the conditions that the vaporization removal of a residue will not oxidize. Therefore, in order to suppress oxidation, the atmosphere of the drying treatment is preferably at least 3% hydrogen, preferably at least 30% hydrogen, and more preferably at least 90% hydrogen.

Further, in the drying treatment, it is preferable to carry out at a temperature and time at which moisture can be vaporized and removed at least, and the temperature and time at which the hardness of the plating layer 18 becomes 80% or less of the maximum hardness or becomes HV750 or less. It is preferable to perform at.

Here, the cause of cracking in the plating layer 18 will be described. For example, in the case where the NiP plating layer is taken as an example, the plating layer 18 itself increases in hardness, ductility decrease, dimensional shrinkage, etc. due to aging precipitation of the plating layer 18. Occurs. As a result, a crack cannot arise because a thermal stress difference with the composite material 16 which is a base material cannot be followed. It has been found that this age precipitation occurs in the thermal history of the drying treatment performed after the plating treatment, for example.

Therefore, in order to prevent the crack from generating in the plating layer 18, it is preferable to carry out by the heating program based on the temperature and time which satisfy | fill the above-mentioned conditions. Specifically, the drying treatment is preferably maintained at an arbitrary temperature of 30 to 600 ° C. for an arbitrary time of 1 to 300 minutes, more preferably at an arbitrary temperature of 200 to 400 ° C. for an arbitrary time of 1 to 300 minutes. It is good to maintain, for more preferably, 1 to 120 minutes at arbitrary temperature of 200-300 degreeC.

In addition, it is preferable to perform the said drying process at the temperature rise rate which does not produce expansion | swelling in the plating layer 18. FIG. In this case, it is preferable that the said temperature rise rate is 400 degrees C / hour or less, More preferably, it is 200 degrees C / hour or less, More preferably, it is 50 degrees C / hour or less.

After the drying treatment in step S8 is completed, the composite material 10A according to the first embodiment is completed, but storage is then performed in step S9, or packed (step S9a: described in parentheses), shipped, for example. It is kept by the user.

Then, if necessary, solder bonding of the stored composite material 10A is performed (step S10).

For example, as shown in FIG. 2, the liquid remaining in the composite material 16 when the insulating substrate 20 is bonded to the heat sink material composed of the composite material 16 via the solder layer 24. (Cutting liquid, plating treatment liquid, etc.) is evaporated and flows out as a gas. At this time, the vaporized gas flows out of the portion where the plating layer 18 is not formed, avoiding the plating layer 18 which acts as a resistor in connection with permeation. .

Therefore, in this 1st Embodiment, cracking, expansion, and peeling generate | occur | produce in the plating layer 18 and the void which generate | occur | produces in the solder layer 24 etc. with the outflow of vaporization gas are suppressed.

In addition, at the time of storage, you may pack using high sealing material, such as aluminum foil, Furthermore, you may be able to maintain the quality immediately after sintering process by using a drying agent together. Through this treatment, it is possible to avoid the generation of voids during solder bonding after storage.

Although the case where the plating layer 18 was formed by the electroless plating process was illustrated in the above-mentioned example, you may form other by electrolytic plating process. In this case, the catalyst applying step in step S5 shown in FIG. 3 can be omitted. In addition, the electrolytic plating process performed in step S6 can be performed on conditions as shown to the "(6) electrolytic plating" process of FIG. 5, for example.

Next, the composite material 10B according to the second embodiment will be described with reference to FIG. 9.

As shown in FIG. 9, the composite material 10B according to the second embodiment has substantially the same configuration as the composite material 10A according to the first embodiment described above, but the surface of the composite material 16 A thin plated layer 18a is formed on at least a portion of the surface of the composite material 16 on which a thin plated layer 18b is formed and the thin plated layer 18b is formed, on which at least the solder layer 24 (see FIG. 2) is formed. This is different in that it is formed. Therefore, the laminated surface 16a which consists of the thin plating 18b of the lower layer and the thick plating 18a of the upper layer is formed in the bonding surface 16a of the composite raw material 16. As shown in FIG.

In the composite material 10B according to the second embodiment, when the insulating substrate 20 is bonded to the heat sink material composed of the composite material 16 via the solder layer 24, the composite material 16 is bonded to the composite material 16. The remaining liquid (cutting liquid, plating liquid, etc.) is vaporized and flows out as a gas. At this time, the vaporized gas avoids the portion where the laminated plating layer 18, which acts as a resistor in relation to permeation, is formed and the thin plating layer 18b is formed. ) Flows out through the formed part.

Therefore, also in this 2nd Embodiment, a crack, an expansion, peeling generate | occur | produces in the laminated plating layer 18, and a void generate | occur | produces in the solder layer 24 etc. with the outflow of vaporization gas, etc. are suppressed.

In particular, in the second embodiment, since the thin plating layer 18b is formed on the surface, handling at the time of soldering is good, and the appearance is also good, and moisture absorption can be reduced.

Next, the specific example (2nd manufacturing method) of the manufacturing method of the composite material 10B which concerns on this 2nd Embodiment is demonstrated, referring FIGS. 4-7, 9, and 10. FIG. In addition, the part which overlaps with the above-mentioned 1st manufacturing method ends with a brief description.

First, the composite material 16 is manufactured in step S101 of FIG. 10, and then preprocessed to the composite material 16 in step S102. As this pretreatment, for example, as shown in the "(2) pretreatment" process of FIG. 4, an alkali degreasing process and a cleaner conditioner process are mentioned.

Thereafter, in step S103 of FIG. 10, the surface of the composite material 16 is activated. Examples of the activation process include an etching process and an pickling process, as shown in the “(3) Activation 1” process of FIG. 4.

In the case where the electroless plating treatment is performed after that, the metal catalyst is applied to the surface of the composite material 16 in step S104 of FIG. 10 before the electroless plating treatment. The conditions (chemical, concentration, temperature) to impart this metal catalyst are shown in the "(4) catalyst provision" process column of FIG. 4, for example.

In addition, when performing an electrolytic plating process instead of an electroless plating process, the above process (step S104) can be skipped. Therefore, in FIG. 10, step S104 is described in parentheses.

Thereafter, electroless plating is performed in step S105 to form a thin plating layer 18b on the surface of the composite material 16 as shown in FIG. Examples of the electroless plating treatment include an electroless plating treatment of NiP in the “(5) Electroless Plating” step of FIG. 5.

The thickness t2 of the thin plating layer 18b is preferably a thickness at which the residual liquid tends to be vaporized and removed, and at least a thickness that is more likely to pass the vaporization gas of the residual liquid than the thick plating layer 18a (see FIG. 9).

In view of the permeability (leakage) of the vaporized gas, the leakiness of the thin plated layer 18b is preferably 5.0 × 10 ⁻¹⁰ cc-atm / sec or more, more preferably 1.0 × 10 ⁻⁹ cc-atm / sec or more. It is good.

Specifically, the thickness t2 of the thin plating layer 18b is 10 µm or less, preferably 5 µm or less, and more preferably 3 µm or less.

Thereafter, in step S106, the composite material 16 having the thin plating layer 18b formed on the surface thereof is subjected to a drying treatment. As shown in the "(8) drying" process of FIG. 6, this drying process is what performs this drying, after performing preliminary drying.

Thereafter, in step S107 of FIG. 10, masking is performed on the composite material 16 having the thin plating layer 18b formed on the surface thereof. For example, as shown in the "(9) masking" process of FIG. 6, this masking is the surface except the joining surface 16a among the surfaces of the composite material 16 in which the thin plating layer 18b was formed (for example, lower surface and Stick the masking tape on the four sides). Of course, you may use a photoresist film etc. instead of a masking tape.

Thereafter, in step S108, the masked composite material 16 is pretreated. As this pretreatment, for example, as shown in the "(10) pretreatment" process of FIG. 6, an alkali degreasing process and a cleaner conditioner process are mentioned. Examples of chemicals, concentrations, and temperatures used in this pretreatment are shown in FIG. 6.

Thereafter, in step S109 of FIG. 10, the surface of the composite material 16 is activated. As this activation process, for example, as shown in the "(11) activation 2" process of FIG. 6, cyanation activation process is mentioned. Examples of the chemicals, concentrations, and temperatures used in this activation treatment are shown in FIG. 6.

Then, in the case where the electroless plating treatment is performed thereafter, at least the bonding surface 16a (the thin plating layer 18b of the composite material layer 16) of the composite material 16 is exposed in step S110 in FIG. 10 before the electroless plating treatment. ] To the metal catalyst. The conditions (chemical, concentration, temperature) to impart this metal catalyst are shown in, for example, the "(12) catalyst provision" process column of FIG. In addition, when electrolytic plating is performed instead of electroless plating, the above process (step S110 of FIG. 10) can be omitted as described later.

Thereafter, electroless plating is performed in step S111, and a thick plating layer 18a is formed on at least the bonding surface 16a (the surface where the thin plating layer 18b is exposed) of the composite material 16, as shown in FIG. To form. This electroless plating treatment is, for example, performing electroless plating treatment of NiB after performing the electroless plating treatment of NiP as shown in the "(13) electroless plating" process of FIG. The conditions of these electroless plating processes are described in FIG.

By this plating process, the laminated plating layer 18 which consists of a thin plating layer 18b and the thick plating layer 18a is formed in the bonding surface 16a of the composite raw material 16. As shown in FIG.

The thickness t of the laminated plating layer 18 (= t1 + t2: see FIG. 9) is similar to that of the plating layer 18 of the composite material 10A according to the first embodiment, and the thickness of the liquid remaining in the composite material 16 It is preferable to have a thickness which does not permeate | transmit vaporization gas through the laminated plating layer 18, or the thickness which can cover the open pores which exist in the composite raw material 16. FIG. Specifically, it is 5-100 micrometers, Preferably it is 5-50 micrometers, More preferably, it is 5-30 micrometers, More preferably, it is 15-25 micrometers.

Then, the peeling process of a masking tape is performed in step S112 of FIG. By this treatment, as shown in FIG. 9, the laminated plating layer 18 remains on the joint surface 16a of the composite material 16, and the thin plating layer 18b is disposed on the lower surface and four side surfaces of the composite material 16. This remains.

After that, in step S113, the composite material 16 having the laminated plating layer 18 formed on the joint surface 16a is subjected to a drying process. As this drying process, as shown in the "(16) drying" process of FIG. 7, for example, this drying is performed after the preliminary drying. The conditions of predrying and this drying are shown in FIG.

Since the preferable aspect (atmosphere, hardness, temperature, time, temperature rise rate, etc.) of the drying process in said S106 step and S113 step is the same as that of 1st Embodiment mentioned above, the duplication description is abbreviate | omitted here.

After the drying treatment in step S113 is completed, the composite material 10B according to the second embodiment is completed. After that, storage is performed in step S114, or packing (step S114a: described in parentheses) is shipped. For example, it is stored by the user.

Then, if necessary, solder bonding of the stored composite material 10B is performed (step S115).

In the above-mentioned example, although the thin plating layer 18b and the thick plating layer 18a were formed together by the electroless plating process, the thin plating layer 18b was formed by the electroless plating process, and the thick plating layer 18a was carried out. May be formed by an electrolytic plating treatment. Of course, you may form the thin plating layer 18b and the thick plating layer 18a together by the electroplating process. When performing an electrolytic plating process, the catalyst provision process in step S104 or S110 shown in FIG. 10 can be skipped. In the case where the thin plating layer 18b is formed by the electrolytic plating treatment, for example, the thin plating layer 18b can be performed under the conditions shown in the "(6) Electrolytic plating" process of FIG. 5, and when the thick plating layer 18a is formed by the electrolytic plating treatment. For example, it can be performed on conditions shown in the "(14) electrolytic plating" process of FIG.

Next, another specific example (manufacturing method according to a modification) of the manufacturing method of the composite material 10B according to the second embodiment will be described with reference to FIGS. 11 and 12.

Although the manufacturing method which concerns on this modification includes the process substantially the same as the 2nd manufacturing method mentioned above, the masking process of step S107 is different. Specifically, as illustrated in FIG. 12, when a pair of blocks 16B is formed by stacking two composite materials 16 on which a thin plating layer 18b is formed on the surface, the block 16B is a pair of blocks 16B. Are arranged so that these various blocks 16B are accommodated in the frame 50, and are put into the next step in this state.

That is, each composite material 16 hides the surface (lower surface and four side surfaces) other than one surface (bonding surface 16a) of each composite raw material 16 by the adjacent composite raw material 16 or the frame 50 so that each composite material can be hidden. It is set as the form which only the joining surface 16a was exposed in the raw material 16. FIG. Of course, you may inject into the next process in the state of the said block 16B which consists of two composite materials 16 combined.

Subsequently, pretreatment of step S108, activation of step S109, activation of step S110, and provision of catalyst of step S110 (omitted in the case of performing electrolytic plating thereafter), plating of step S111 (formation of thick plating layer 18a) are performed. As a result, as shown in FIG. 9, the thick plating layer 18a is formed only on the joint surface 16a of the composite material 16. By this plating process, the laminated plating layer 18 which consists of the thick plating layer 18a and the thin plating layer 18b is formed in the bonding surface 16a of the composite raw material 16. As shown in FIG.

Thereafter, in step S112 of FIG. 11, the frame 50 shown in FIG. 12 is disassembled or removed to separate the blocks 16B into individual composite materials 16. Thereafter, the composite material 10B according to the second embodiment is obtained through the drying treatment in step S113.

In this method, it is advantageous in terms of cost because only the frame 50 is prepared, which eliminates the need for masking tape. In addition, it is possible to process a plurality of composite materials 16 at once, which is advantageous for reducing the number of processes. Done.

Next, the composite material 10C according to the third embodiment will be described with reference to FIG. 13.

As shown in FIG. 13, the composite material 10C according to the third embodiment has a configuration substantially the same as that of the composite material 10B according to the second embodiment described above. A thick plating layer 18a is formed directly on the portion where the solder layer 24 (see FIG. 2) is formed (bonding surface 16a), and the surface of the composite material 16 on which the thick plating layer 18a is formed (thick). Including the surface of the plating layer 18a], a thin plating layer 18b is formed. Therefore, a laminated plating layer 18 composed of a lower thick plating layer 18a and an upper thin plating layer 18b is formed on the joint surface 16a of the composite material 16.

In the composite material 10C according to the third embodiment, similar to the composite material 10B according to the second embodiment, the heat sink material composed of the composite material 16 is insulated through the solder layer 24. When joining the substrate 20, the liquid remaining in the composite material 16 (cutting liquid, plating treatment liquid, etc.) is vaporized and flows out as a gas. At this time, the vaporized gas acts as a resistor in connection with permeation. Avoiding the portion where the laminated plating layer 18 is formed, it flows out through the portion where the thin plating layer 18b is formed.

Therefore, also in this 3rd Embodiment, a crack, an expansion, peeling generate | occur | produces in the laminated plating layer 18, the void generate | occur | produces in the solder layer 24, etc. with the outflow of vaporization gas, etc. are suppressed.

Moreover, also in this 3rd Embodiment, since the thin plating layer 18b was formed in the surface, handling at the time of soldering becomes favorable, it is also favorable externally, and moisture absorption can also be reduced.

Next, the specific example (third manufacturing method) of the manufacturing method of the composite material 10C which concerns on this 3rd Embodiment is demonstrated, referring FIGS. 4-7 and FIG. At this time, the part overlapping with the 2nd manufacturing method mentioned above is demonstrated easily.

First, the composite raw material 16 is produced in step S201 of FIG. 14, and then the composite raw material 16 is masked in step S202. This masking is performed by affixing a masking tape on the surface (for example, lower surface and four side surfaces) except the bonding surface 16a among the surfaces of the composite raw material 16. Of course, a photoresist film or the like may be used instead of the masking tape.

Thereafter, the composite material 16 is subjected to pretreatment (alkali degreasing treatment and cleaner conditioner treatment) in step S203, and then the surface of the composite material 16 is activated (etching treatment and pickling treatment) in step S204.

And when electroless plating process is performed after that, a metal catalyst is provided to the joining surface 16a of the composite raw material 16 and the surface of a masking tape in step S205 before an electroless plating process. In addition, when performing an electrolytic plating process instead of an electroless plating process, the said process (step S205) can be skipped as mentioned above.

Thereafter, electroless plating is performed in step S206 to form a thick plating layer 18a on the joint surface 16a of the composite material 16 and the surface of the masking tape. Examples of this electroless plating treatment include performing electroless plating of NiB after performing electroless plating of NiP as shown in the “(5) Electroless Plating” process of FIG. 7. The thickness of the thick plating layer 18a is preferably 5 to 100 µm, preferably 5 to 50 µm, more preferably 5, similarly to the thickness of the thick plating layer 18a of the composite material 10B according to the second embodiment. It is -30 micrometers, More preferably, it is 15-25 micrometers.

Then, the peeling process of a masking tape is performed in step S207. By this treatment, the thick plating layer 18a remains only on the joint surface 16a of the composite material 16. After that, in step S208, the composite material 16 on which the thick plating layer 18a is formed on the bonding surface 16a is subjected to drying treatment (preliminary drying treatment and main drying treatment).

Thereafter, in step S209, the composite material 16 after drying is subjected to pretreatment (alkali degreasing treatment and cleaner conditioner treatment), and then, in step S210, the surface of the composite material 16 is activated (cyanide activated treatment).

Then, in the case where the electroless plating treatment is performed thereafter, the metal catalyst is applied to the surface of the composite material 16 (including the surface of the thick plating layer 18a) in step S211 before the electroless plating treatment. In addition, when electrolytic plating process is performed instead of electroless plating process, the said process (step S211) can be skipped as mentioned later.

Thereafter, electroless plating is performed in step S212 to form a thin plating layer 18b on the surface of the composite material 16 (including the surface of the thick plating layer 18a), as shown in FIG. By this plating process, the laminated plating layer 18 which consists of the thick plating layer 18a and the thin plating layer 18b is formed in the bonding surface 16a of the composite raw material 16. As shown in FIG.

Thereafter, in step S213, the drying treatment (preliminary drying treatment and main drying treatment) is performed on the composite material 16 having the laminated plating layer 18 formed on the bonding surface 16a.

Since the preferable aspect (atmosphere, hardness, temperature, time, temperature increase rate, etc.) of the drying process in said S208 step and S213 step is the same as that of 1st Embodiment mentioned above, the duplication description is abbreviate | omitted here.

After the drying treatment in step S213 is completed, the composite material 10C according to the third embodiment is completed, but storage is then performed in step S214, or packing (step S214a: described in parentheses), and shipped. For example, it is stored by the user.

Then, if necessary, solder bonding of the stored composite material 10C is performed (step S215).

In the above-mentioned example, although the thick plating layer 18a and the thin plating layer 18b were formed together by the electroless plating process, the thick plating layer 18a was formed by the electroless plating process, and the thin plating layer 18b was formed. ) May be formed by electroplating. Of course, the thick plating layer 18a and the thin plating layer 18b may be formed together by the electroplating process. In the case of performing the electrolytic plating treatment, the catalyst applying step in step S205 or step S211 shown in FIG. 14 can be omitted.

Next, the composite material 10D according to the fourth embodiment will be described with reference to FIG. 15.

The composite material 10D according to the fourth embodiment has a structure substantially the same as that of the composite material 10A according to the first embodiment described above. However, as shown in FIG. 15, the composite material 10D is formed on the surface of the composite material 16. A portion of the formed plating layer 18 (eg, a portion corresponding to the lower surface of the composite material 16 and / or a portion corresponding to four side surfaces) is etched or polished, and a portion of the plating layer 18 is thinned. It is different in that it is.

In the composite material 10D according to the fourth embodiment, similarly to the composite material 10B according to the second embodiment, the heat sink material composed of the composite material 16 is insulated through the solder layer 24. When joining the substrate 20, the liquid remaining in the composite material 16 (cutting liquid, plating liquid, etc.) is vaporized and flows out as a gas, where the vaporized gas acts as a resistor in connection with permeation. Avoiding the portion where the plating layer 18 is formed, the plating layer 18 flows out through the thinned portion.

Therefore, also in this 4th embodiment, a crack, an expansion, peeling generate | occur | produces in the plating layer 18, and a void generate | occur | produces in the solder layer 24 etc. with the outflow of vaporization gas, etc. are suppressed.

Also in this fourth embodiment, since the plating layer 18 is formed on the surface, handling at the time of soldering is good, appearance is also good, and moisture absorption can be reduced.

Next, the specific example (fourth manufacturing method) of the manufacturing method of the composite material 10D which concerns on this 4th Embodiment is demonstrated, referring FIG. Here, the part overlapping with the 1st manufacturing method mentioned above is demonstrated easily.

First, the composite material 16 is produced in step S301 of FIG. 16, and then the composite material 16 is pretreated (alkali degreasing treatment and cleaner conditioner process) in step S302, and then the composite material 16 in step S303. The surface of the surface is activated (etched and pickled).

And when electroless plating process is performed after that, a metal catalyst is provided to the surface of the composite raw material 16 in step S304 before the electroless plating process. In addition, when electrolytic plating is performed instead of electroless plating, the above process (step S304) can be omitted.

Thereafter, electroless plating is performed in step S305 to form the plating layer 18 on the surface of the composite material 16 as shown in FIG.

As described above, the thickness t of the plating layer 18 is the same as that of the plating layer 18 of the composite material according to the first embodiment, and the vaporization gas of the liquid remaining in the composite material 16 is formed in the plating layer 18. It is desirable to have a thickness such that it does not penetrate or a thickness capable of covering the open pores present in the composite material 16. Specifically, it is 5-100 micrometers, Preferably it is 5-50 micrometers, More preferably, it is 5-30 micrometers, More preferably, it is 15-25 micrometers.

Thereafter, in step S306, the partial processing is performed on the plating layer 18 formed on the surface of the composite material 16. This treatment is carried out by etching or polishing a part of the plating layer 18 formed on the surface of the composite material 16 (for example, a portion corresponding to the bottom surface of the composite material 16 and / or a portion corresponding to four sides). By processing, a part of the plating layer 18 is thinned.

The thickness t2 of the thinned plating layer 18 is preferably a thickness at which the residual liquid is easily vaporized and removed, and at least a thickness that allows the vaporizing gas of the residual liquid to pass through at least than the plating layer 18 of the bonding surface 16a. Specifically, it is 10 micrometers or less, Preferably it is 5 micrometers or less, More preferably, it is 3 micrometers or less.

After that, in step S307, the composite material 16 having the plating layer 18 formed on its surface is subjected to drying treatment (preliminary drying treatment and main drying treatment). Since the preferable aspect (atmosphere, hardness, temperature, time, temperature increase rate, etc.) of this drying process is the same as that of 1st Embodiment mentioned above, the duplication description is abbreviate | omitted here.

After the drying treatment in step S307 is completed, the composite material 10D according to the fourth embodiment is completed, but then storage is performed in step S308, or packing (step S308a: described in parentheses), and shipped. For example, it is stored by the user.

Then, if necessary, solder bonding of the stored composite material 10D is performed (step S309).

Although the case where the plating layer was formed by the electroless-plating process was mentioned in the above-mentioned example, you may form other by electrolytic plating process. In this case, the catalyst applying step in step S304 shown in FIG. 16 can be omitted.

Next, one experimental example is illustrated. In this experimental example, in Comparative Example 1, Comparative Example 2 and Examples 1 to 4 described in FIG. 17, the crack generation state in the plating layer 18, the expansion of the plating layer 18, The peeling state and the void generation state were observed.

In Comparative Example 1, the plating layer 18 (NiP plating layer: 18 µm, NiB plating layer: 2 µm) having a thickness of 20 µm was formed on both surfaces (or surfaces) of the composite material 16 by the electroless plating treatment using the first production method described above. After forming, it shows the case where it is dried.

In Comparative Example 2, a 2.5 μm plating layer 18 (NiP plating layer: 1.5 μm, NiB plating layer: 1.0 μm) was formed on both surfaces (or surfaces) of the composite material 16 by the electroless plating treatment using the first manufacturing method described above. After forming, it shows the case where it is dried.

In Example 1, the plating layer 18 (NiP plating layer: 17 micrometers, NiB plating layer: 3 micrometers) of 20 micrometers only in the bonding surface 16a of the composite material 16 by an electroless plating process by the 1st manufacturing method mentioned above. After forming, it shows the case where it is dried.

In Example 2, after forming the plating layer 18 (Ni plating layer: 20 micrometers) of 20 micrometers only in the bonding surface 16a of the composite material 16 by the electrolytic plating process by the above-mentioned 1st manufacturing method, it is a drying process. One case is shown.

In Example 3, the plating layer 18b (NiP plating layer) of 1 µm is formed on both surfaces (or surfaces) of the composite material 16 by the electroless plating treatment by the second manufacturing method (or the manufacturing method according to the modification) described above. 1 탆), followed by drying, and then electroless plating treatment followed by a 19 탆 plating layer 18a (NiP plating layer: 17 탆, NiB plating layer: 2 탆) only on the joint surface 16a of the composite material 16. ) Is shown after drying.

In Example 4, a plating layer 18b (NiP plating layer: 1 µm) having a thickness of 1 µm was formed on both surfaces (or surfaces) of the composite material 16 in the same manner as in Example 3, followed by drying and electrolytic plating. The case where 19 micrometers plating layer 18a (Ni plating layer) is formed only in the bonding surface 16a of the composite raw material 16, and is dried is shown.

Each above-mentioned drying process was performed by maintaining preliminary drying at the temperature of 60 degreeC for 120 minutes, and then maintaining this drying at the temperature of 260 degreeC for 10 minutes (ambient of 100% hydrogen).

The result of this experimental example is shown in FIG. In this FIG. 18, a plating crack item shows the crack state in the plating layer 18, (circle) shows a non-occurrence, and (x) generate | occur | produces a bad state. The expansion and peeling items indicate an expansion or peeling state of the plating layer 18, and ○ indicates no occurrence and × indicates a poor state.

The void item shows the void generation state in a solder layer as a percentage by the following formula | equation. In addition, the total area and solder joint area of a void part were measured with the X-ray transmission photograph.

Void rate (%) = (total area of solder part / solder joint area) × 100

From the result of FIG. 18, plating crack did not generate | occur | produce anywhere in Comparative Example 1, Comparative Example 2, and Examples 1 to 4, but a lot of expansion and peeling occurred in Comparative Example 1.

Regarding the void ratio, Comparative Example 1 and Comparative Example 2 are both practically 1.0 to 2.0% immediately after completion of the composite material 16, but are sufficiently practical, but increase to 10.0 to 20.0% after storage, indicating that the quality is deteriorated. Able to know.

On the other hand, in Examples 1 to 4, it is understood that the void ratios immediately after completion of the composite material 16 and after storage are both low values of 1.0 to 2.0% and the quality is stable.

And the composite material which concerns on this invention, and its manufacturing method are not limited to embodiment mentioned above, Of course, various structures can be employ | adopted without deviating from the summary of this invention.

As described above, according to the composite material and the manufacturing method thereof, when the plated composite material is bonded to another object by a bonding layer such as a solder layer, cracking, swelling, or peeling of the plating layer occurs. It can suppress that a void generate | occur | produces in a bonding layer.

Claims (40)

A composite material having a composite material impregnated with a porous sintered body and bonded to another object by a bonding layer, A composite material, wherein a plating layer is formed on at least a portion of the surface of the composite material in which the bonding layer is formed. The composite material according to claim 1, wherein the plating layer is composed of only the first plating layer or the first plating layer and the second plating layer. The composite material according to claim 2, wherein the first plating layer is formed on at least a portion of the surface of the composite material in which the bonding layer is formed, and the second plating layer is formed on other portions thereof. The composite material according to claim 2, wherein the first plating layer is formed on at least a portion of the surface of the composite material in which the bonding layer is formed, and the second plating layer is not formed on other portions. The composite material according to any one of claims 2 to 4, wherein a void rate generated in the bonding layer is 3% or less by vaporization gas that passes through the first plating layer. The composite material according to any one of claims 2 to 4, wherein the leakage property of the first plating layer is 5.0 x 10 ^-10 cc-atm / sec or less. The composite material according to any one of claims 2 to 4, wherein the first plating layer covers 90% or more of open pores existing on the surface of the composite material in an area ratio. The composite material according to any one of claims 2 to 4, wherein the first plating layer is a layer by electroless plating, and there is no plating crack. The composite material according to any one of claims 2 to 4, wherein the first plating layer is a layer by electroless plating, and the hardness is 80% or less of the maximum hardness. The composite material according to any one of claims 2 to 4, wherein the first plating layer is a layer by electroplating. The composite material according to any one of claims 2 to 4, wherein the first plating layer is composed of a layer by electroless plating and a layer by electrolytic plating. The composite material according to any one of claims 2 to 4, wherein the first plating layer has a thickness such that the vaporizing gas does not permeate. The composite material according to any one of claims 2 to 4, wherein the first plating layer has a thickness of at least twice the diameter of the open pores existing on the surface of the composite material. The composite material according to any one of claims 2 to 4, wherein the first plating layer has a thickness of 5 to 100 µm. The composite material according to any one of claims 2 to 4, wherein the first plating layer has a thickness of 5 to 50 µm. The composite material according to any one of claims 2 to 4, wherein the second plating layer has a thickness in which the residual liquid is easily vaporized and removed. The composite material according to any one of claims 2 to 4, wherein the second plating layer is more likely to permeate the vaporization gas of the residual liquid than at least the first plating layer. The composite material according to any one of claims 2 to 4, wherein the second plating layer has a thickness of 10 µm or less. The composite material according to any one of claims 2 to 4, wherein the second plating layer has a thickness of 5 µm or less. The composite material according to any one of claims 2 to 4, wherein the leakage property of the second plating layer is 5.0 x 10 ^-10 cc-atm / sec or more. The composite material according to any one of claims 2 to 4, wherein the second plating layer is an electroless plating, an electrolytic plating, or both thereof. A method for producing a composite material having a composite material in which a porous sintered body is impregnated with metal and bonded to another object by a bonding layer, A plating layer is formed on at least the part of the surface of the said composite material in which the said bonding layer is formed, The manufacturing method of the composite material characterized by the above-mentioned. 23. The method of producing a composite material as defined in claim 22, wherein the plating layer is formed of only the first plating layer or from the first plating layer and the second plating layer. 24. The method of manufacturing a composite material according to claim 23, wherein the first plating layer is formed on at least a portion of the surface of the composite material in which the bonding layer is formed, and the second plating layer is formed on other portions thereof. . The composite material according to claim 23, wherein the first plating layer is formed on at least a portion of the surface of the composite material in which the bonding layer is formed, and the second plating layer is not formed on other portions. Way. The manufacturing method of the composite material of any one of Claims 23-25 which includes the process of masking on the surface other than the part which forms said 1st plating layer. The process of any one of Claims 23-25 after forming said 2nd plating layer, and then masking to 2nd plating layers other than the part which forms said 1st plating layer, and then forming a 1st plating layer. Method for producing a composite material comprising a. The composite material according to any one of claims 23 to 25, wherein the first plating layer and the second plating layer are formed by repeating a series of processes n times of drying after the plating treatment is performed n times. Way. 29. The method of producing a composite material as defined in claim 28, wherein said drying treatment is carried out at a temperature and for a time capable of vaporizing and removing at least moisture. 29. The method of producing a composite material as defined in claim 28, wherein the drying treatment is held at an arbitrary temperature of 30 to 600 DEG C for any time of 1 to 300 minutes. 29. The method of producing a composite material as defined in claim 28, wherein the drying treatment is held at an arbitrary temperature of 200 to 400 [deg.] C. for an arbitrary time of 1 to 300 minutes. The method for producing a composite material according to claim 28, wherein the drying treatment is performed in an atmosphere of suppressing oxidation of the plating layer. 33. The method of claim 32, wherein the atmosphere is selected from an inert gas atmosphere, a vacuum atmosphere and a reducing atmosphere. 34. The method of producing a composite material as defined in claim 33, wherein the reducing atmosphere is an atmosphere in which hydrogen is at least 3%. 34. The method of producing a composite material as defined in claim 33, wherein the reducing atmosphere is at least 30% hydrogen. 34. The method of producing a composite material as defined in claim 33, wherein said reducing atmosphere is at least 90% hydrogen. 29. The method of producing a composite material as defined in claim 28, wherein said drying treatment is performed at a rate of temperature rise that does not cause expansion in said first plating layer and said second plating layer. 38. The method of producing a composite material as defined in claim 37, wherein the rate of temperature rise is 400 ° C / hour or less. 38. The method of producing a composite material as defined in claim 37, wherein the rate of temperature rise is 100 ° C / hour or less. 29. The method of producing a composite material as defined in claim 28, wherein said drying treatment is performed by a heating program maintained near the vaporization temperature of the residual liquid.